One of Android's best and most oft-overlooked features is its ability to switch out the default keyboard for an alternative. These come with extra, innovative features and are a vast improvement on the stock keyboards.

There are hundreds on the Play Store, too, and you can change keyboards until you find one you like. With this in mind, we've selected nine of the best keyboards available on Android devices.

But before you download them, it's a good idea to work out what sort of typist you are. Some people love swanky swipe interfaces, whereas others feel more comfortable with more tactile traditional keyboards. On top of those are some really odd keyboards which do something a little different.

Switching between the various keyboards can be a bit of a pain, but if you tap the menu key on your device, choose "Settings" and then go to "Language & keyboard" you'll be able to choose which ones are active, and which one is currently set as the default.

Smart Keyboard

Smart Keyboard doesn't include any gimmicks such as predictive phrases or swipe-based typing, but it's a solid and substantial offering nevertheless. There's a free trial available on the Play Store, and the only difference between this and the full version (£1.96) is an occasional nag screen to annoy you into buying it.

A really nice feature of Smart Keyboard is the ability to adjust the height of the keys. With other keyboards this is done with some pre-defined defaults, but Smart Keyboard uses sliders for an infinitesimal degree of customisation. This means you can have nice big keys if you struggle to see or hit standard ones, or really small ones if you want to increase your screen's real estate.

Smart Keyboard ships with an iPhone-style keyboard by default, and it works just as well as Apple's sleek and fluid option. There are other options for specific devices such as HTC or Galaxy smartphones, as well as standard Android offerings.

If you really want to get your hands dirty it supports an open-source keyboard format which means you can create your own, and even use these with other keyboards.

Download this if... You want big or small keys

Avoid this if... You don't like gimmicks

Verdict: 4/5

Adaptxt

If there was an award for best-looking keyboard, Adaptxt would win it hands - or fingers - down. Its spacious and airy layout and translucent graphics make it look and feel like something you'd find on a premium laptop - albeit in a virtual form.

Adaptxt also includes a handful of incredibly useful features. At the time of writing the Olympics are about to begin, and typing sports-related keywords lights a lightbulb icon at the bottom of the screen which takes you straight to the relevant Wikipedia page. There's also an incredibly handy option to post whatever you're writing straight to Twitter or Facebook without having to launch the relevant apps, which is great if you're midway through a witty text or email.

On top of that there's the ability to remove accents and diacritics, which add extra characters to text messages - something we naively didn't realise.

Adaptxt is an innovative and super-smart keyboard, and one of the best we've come across. There's even a private mode so certain words and phrases won't be stored in its dictionary, making it ideal if you share your phone or tablet with someone else.

Download this if... You want an innovative, good-looking keyboard

Avoid this if... You hate new things

Verdict: 5/5

SwiftKey

SwiftKey has been our default keyboard for many years, and it's just got better and better. Its unique selling point is its ability to predict what you're about to type based on previous emails, texts, Facebook updates and Tweets, and it works remarkably well. In fact, it's almost spooky in the way it works out what you're about to type next.

The result is that you barely even have to try to type, and you soon realise that most of your communications consist of a few key words or phrases. It's astonishingly quick for exactly this reason, although we can understand some people's reluctance to let the software sift through all your private emails and texts.

There are a few problems, notably one with the Chrome browser which is being worked on at the time of writing. It also only comes with a handful of skins and the layout can't be customised. There's a dedicated tablet version of SwiftKey, but this has to be bought separately on the Android Market.

Somehow, though, Swiftkey is still out favourite keyboard, if only for the fact that it makes entering text on a wee screen so incredibly easy.

Download this if... You want fast, accurate text input

Avoid this if... You don't like the idea of it looking through personal data